This invention relates to apparatus for cleaning debris such as clay, dirt or stones, from between the flightings of an earth auger as the auger is being removed from a borehole while continuing to rotate in the forward direction.
One typical auger for drilling bore holes is illustrated in U.S. Pat. No. 4,966,498 (incorporated by reference). As schematically depicted in that patent, an auger is suspended from an upright, box-like support frame which rests on the ground and extends upwardly from the area in which a bore hole is to be drilled. A crane or other similar unit may be employed to maintain the upright frame in its essentially vertical disposition. Other variants of the auger support frame are utilized, such as a variant where the auger is surrounded (in whole or part) by the auger support frame (see FIG. 1).
As the auger is rotated about its longitudinal axis in a drilling or xe2x80x9cforwardxe2x80x9d direction (xe2x80x9cforwardxe2x80x9d is clockwise rotation on most augers causing the auger to bite into and dig a bore hole in the ground), the auger drills a bore hole and clay or dirt loosened by the auger is brought to the surface of the ground through the auger""s flighting and is deposited in the area surrounding the auger. When a borehole of required depth has been formed, the auger is lifted from the hole while rotation thereof is continued in order to continue to lift loosened dirt. Typical auger holes range from 12-inches in diameter up to 48-inches in diameter.
Bore holes formed in the ground for piers are usually deep and are dug with an auger that is made up of a number of connected, end-to-end auger sections. Each auger section has a length designed for ease of transportation on a truck bed and for ease of handling and assembly in the field. Generally, one auger section threads into the adjacent auger section. The end of the shaft of the auger where a connection is formed is generally slightly thickened to accommodate the threaded connection.
Upon extraction of the auger from a borehole, some of the dirt, clay and other accumulation accumulated in the flighting (the xe2x80x9cflightingxe2x80x9d is considered the volume between adjacent spirals of the auger flight) will be thrown from the auger, and some dirt and clay will remain trapped in the flighting, particularly when working in heavy clays which can substantially fill the spiral space defined by the auger flights. Generally, the flighting can be cleaned by xe2x80x9chandxe2x80x9d using boards to knock the material loose from the flightings, or a mechanical device can be used, such as disclosed in U.S. Pat. No. 5,242,027 or U.S. Pat. No. 3,968,846, both of which are incorporated by reference.
Both of these mechanical devices interpose a wheel with daisy-like lobes rotatable on a first shaft. The wheel""s lobes are interposed between the flightings for cleaning the flightings by scrapping this area. The device is designed to allow the wheel, upon encountering debris that cannot be removed by scraping, to xe2x80x9ckick outxe2x80x9d away from between the flightings on an axis different from that of the first shaft. Such movement prevents the device from becoming damaged upon encountering debris that the device is incapable of removing. Both devices, however, are cumbersome, using an articulated arm to position the daisy wheel into engagement and disengagement from the auger""s flight paths.
The apparatus of this invention is a single shaft having a disk with lobes that intermesh with the flightings of an auger, the disk positioned on the shaft to allow rotation of the disk about the shaft, a stop positioned on the shaft on one side of the disk and a spring positioned on the shaft on the other side of the disk to position the disk adjacent to the stop. The shaft is mounted to the support frame of the auger through a mount means.